Expansible chamber fluid motor or pump



March l5, 1949; c, M BOLSTER 2,464,208

FLUID MOTOR OR PUMP Filed oct. 31. 1945 s. shets-sheet 1 March 15, 1949.

ci. M. BoLs'rER 24,464,208

EXPANSIBLE CHAMBER FLUID MOTOR OR PUMP Filed Oct. 31, 1945 3 Sheets-Sheet 2 'lllllrllllllllnrll March l5, 1949. c. M. BoLs'rER 2,464,208

EXPANSIBLE CHAMBER FLUID MoToR'oR- PUMP Filed Oct. 31, 1945 3 Sheets-Sheet 5 gt 01N .s v M u n m m. W i?? s E E =E25: =:A W/ 4 m a FW l .M Y. l WW/w .www

Patented .Man 15, 19.49

UNITED sfraTlszsA PATENT ,OFFICE calvin M. Bolsar, United states Navy-V Application October 31, 1945, Serial No. 625,931

(C1. s-11s) (Granted under the act of March 3, 1883. as

6 Claims.

This invention relates to an improved expansible chamber iluid motor or pump.

An object of this invention is to provide a fluid device having a, plurality of expansible chambers, several oi' which are always lling while the remainder are exhausting, and each of the said chambers iills and exhausts once during each revolution of the said device.

A further object of this invention is to provide a uid motor that will give a high torque load.

A still further object of this invention is to provide a fluid motor that will develop torque the instant pressure is applied to the motor and which will develop its maximum torque arnost instantly.

A yet further object of this invention is to provide a fluid pump that requires a minimum torque load to move a given volume of iluid.

Another object of this invention is to provide a fluid pump, that will move its maximum volume of iiuid almost instantly upon applying torque to the said pump.

Another object of this invention is to Provide a fluid device that has a very large volumetric efciency.

A further object of this invention is to provide a iiuid pump, that when used as a compressor, is capable of handling large volumes at high pressures.

Another object of this invention is to provide a fluid pump or compressor that is capable of handling large volumes of compressible iiuids due to the cooling eilect of the incoming fluid.

Other objects and advantages of this invention will become apparent as the discussion proceeds, and is considered in connection with the accompanying drawings, wherein like characters of reference designate like parts in the several views, and wherein:

Fig. l is a vertical cross-section view of the device embodied in this invention showing the positionof the inlet and outlet ports in relation to the expansible chambers, taken onl the lines I-I of Fig. 2,

Fig. 2 is a longitudinal cross-section view oi the device embodied in this invention taken on the line 2-2 of Fig. 1 showing the position of the inlet and outlet ports in relation to the housing and crank shaft, and

Fig. 3 is a perspective view of both the curved and straight vanes of the device embodied by this invention, showing the hinge' bearings.

Referring now to the drawings, wherein for the purpose of illustration, is shown a preferred embodiment of this invention and wherein like numerals designate like parts throughout, the nuamended April 30, 1928; 370 0. G. 757) merel-8 designates a 4stand or base carrying a. cylindrical housing or case 9 having inner walls I Il which form a cylindrical chamber I I. Circular end plates I2 aflixed to the ends of the housing 9 by bolts I3 complete the closure of the chamber II. Annular fluid passages I4, provided in the 'end plates I2, as shown, admit fluid into the chamber II. Continuous annular recesses I5 located near each end of the cylinder 9, as shown, are provided in the inner walls I0 oi the cylinder 8 and are in open communication with the chal nber II to permit escapement of uid from the cylindrical chamber II through suitable apertures I6. Depending arms I1 are aillxed to the inner walls I0 of the cylinder 9 in any conventional manner, as b y welding or the like, or may, if desired, be cast integral with the cylinder housing, and are located midway the said cylinder between the annular recesses I5. Carried upon the lower end of the depending arms I1 are one-half of a hinge bearing I8. Curved vanes I9 extending laterally the chamber II are pivotally hinged at one end to the hinge bearing I8 by means of a second half of a hinge bearing 20. A pin 2| interconnects the hinge bearings I8 and 20. A second hinge bearing half 22 is provided on the opposite end of the vane I9 and hinges the said vane to a corresponding second half of a hinge bearing 23, provided on a at vane 24. The hinge bearings 22 and 23 are held together by a pin 22a. The said flat vane 24 extends laterally the length of the chamber II, the

4same as the curved vane I9. The curved vane I9 and the iiat vane 24, when assembled for'm one wall of an expansible chamber. A small clearance is provided between the bearings I8 and 20 and also between the bearings 22 and 23, as shown to enable an effective pressure seal to be formed between the bearings. The number of curved vanes I9 and fiat vanes 24 are shown, for the purpose of illustration, to be five, but it is to be understood that the number of such vanes can be varied without departing from the spirit oi' this invention; however, it is recommended that the number be decreased to not less than three.

Two wrist-arms 25 are provided on each of the flat vanes 24, as shown in Fig. 3, and are adapted to carry a crank pin 26. A bushing 21 inserted between the wrists 25, and the crank pin 26 serves as a friction bearing. A small clearance between the at vane 24 and the bushing 21 provides an eiiective pressure seal., The wristarms 25 on each of the ilat vanes 24 are in stag- 'gered relation to permit assembly on the crank pin. Bushings or separators in the form oi :space washers maybe provided to take up any clearance between adjacent wrist-arms to form friction bearings and pressure-type close-clearance seals.

The crank pin 2S is splined at each end to receiveg.

4 being stationarily hinged to the housing 9 at identical circular end plates 28. The said cir- .\5

cular end plates rotate within the chamber II. Each plate 28 carries a shaft 29 rotatably supported by pressure-sealed bearings 30, either of the ball or rotor type, provided in the end plates I2 of the housing; the bearings being eectively" Apressure-sealed by reason of the close clearances at 4I and 42 as shown. On one or both of the to above by the use of well known wiper strips such as shown for example at 43, slidably mounted in a corresponding slot and biased to close the clearance between the bearing surfaces. The present invention however is not concerned with any specific type of pressure sealing means for any of the clearances referred to.

vIn each of the circular end plates, and rotating therewith, is an inlet port 32, in open communication with an annular channel 33 provided circumferentially in each of the plates 28, as shown; the annular channels 33 in turn are in continuous open communication with the annular uid passage I4. The intake ports 32 are identical in each end plateV and are shaped substantially as shown in Fig. 1. The precise cross-sectional area of the said ports will vary with each motor or pump, but the general conguration, as shown, will remain the same. 'I'he leading edge of the inlet port 32 takes the same configuration as the leading face of the curved vane I9 and the bear- More effective pressure seals one end, and hinged to the crank pin 29 at the QPposite end, oscillate as the crank pin rotates Y about the axis of the shaft 29, as shown in Fig. 1. vThis oscillation of the vanes causes the chambers or spaces, formed by the leading surfaces of one set of vanes I9 and 24 and the following V- surfaces of the aaent set of vanes I9 and 24 on the other side, and the inner wall III of the cylinder II on a third side, the crank, pin 26 forming the fourth side, to vary in absolute volume; each of these said chambers (A to E, inclusive, in the preferred embodiment of this invention) varying in volumetric s'ize, from the minimum volume of chamber A tothe maximum volume of chamber B, as shown in Fig. 1, once during each revolution of the shaft.

The inlet valve 32 begins its opening into chamber A, as chamber A is completely exhausted, and is beginning to expand and closes in chamber B. At this same moment, the outlet port ,35 closes in chamber A and opens in chamber B.

When this device is used as a motor, steam or other gas under pressure is carried to the end plates 28 through the annular fluid passage I4 'and'enters 'the spaces A to E at the proper time through the inlet ports 32. It is to be here notedV that the inlet and outlet-ports are disposed in each end of the chamber to relieve both torque on the motor and the thrust on the bearings 30.

Steam or gas enters chamber A as it begins to increase in volume, the shape of the inlet port 'area of the chamber A at its smallest volume as soon as the port opens into the said chamber.

ing I9, as shown by the dotted lines in Fig. 1.

The following edge of the said port 32 takes the same conguration as the following face of the curved vane I9 and the bearing I8. The radial length of the said inlet port is equal to the radial distance from the leading edge or face of one of the said curved vanes I9 to the following edge or face of the second next adjacent curved vane I9 as shown in Fig. 1. The actual width of the said port will vary with the variation in structure of vanes I9 and 24 or the cross sectional area of the spaces formed by the said vanes and the position of the crank pin 29.

Cylindrical flanges or lips 34 carried on the outer circumference of the plates 28, as shown, may be amxed thereto in any conventional manner, as by welding or may be cast integral therewith. In each of these said anges are provided an outlet port 35 as shown in Figs.v 1 and 2 in continuous open communication with the annular recesses I5; the radial length .of the outlet ports is equal to the radial distance from the center of one of the pins 2| to the center of the next adjacent pin, as shown. 'I'he axial width of the said ports varies with the load demand and structural features of each motor or pump.

structurally, when assembled, fiive variable volumetric chambers or spaces A, B, C, Dand E,

. as shown in Fig. 1, are formed by the vanes I9 and 24, acting as walls within the chamber II. When these chambers or spaces, A to E, inclusive, are pressure sealed, each from`the other, five 4,separate pressure-sealed variable volumetric chambers or spaces,ieach having a positive displacement, are formed.

lIn operation, the circular end plates 28 carrying the crank pin 26, rotate on the shafts 29. The at and curved vanes I 9 and 24, respectively,

-lli

AAt this time, the inlet port is also lopen into both Vchamber C and D. Energy from the steam or gas acting upon the curved vanes I9, the ilat vanes 24 and a small portion of the crank pin urge the cylinder A to expand from' its minimum size until it reaches its -maximum size equal to that of cylinder B, as shown. As this expanding takes place, the crank pin is caused to rotate about is axis, which in turn causes the drive shaft 29 to 4rotate about its axis.

It is to be further noted that this device when used as a motor may be converted into a reversible motor by simply reversing the valves which turn the high pressure side of the gas or steam into the recesses I5 and opening the annular uid passages I 4, thereby reversing the direction of the flow of the gas or steam.

When this device is used as a pump or compressor, rotational venergy is translated to the vanes I9 and 24, respectively, through the pulley 3i, the shaft 29, and the crank pin-26'. Fluid is taken into lthe spaces A to E, inclusive, from the annular fluid passages I4, through the inlet ports 32. As the volume of space A is caused to increase in size, iiuid is continuously drawn into the said space until it reaches it maximum volume, that BAB/4,908

the space through the outlet port I5. In a pump or compressor of this nature large volumes of nuid can be .handled easily with a minimum torque load applied to the drive shaft. In event it is desired to use this device als a compressor, the cross-sectional area of the outlet ports may be varied to give the pressure desired.

` While the preferred form of this inventionhas been shown as having the housing stationary and the crankshaft and its assembly rotatable, it is to be understood that the housing can be so constructed as to rotate around a stationary crank. shaft and its assembly, without departing from the spirit of this invention.

The invention described herein may be manu-- factured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

What I claim is:

1. In a fluid transmission device comprising a housing, a pressure chamber therein, a crank shaft rotatably coasting with the said housing, and vanes pivotally connected to the said housing and to the crank'of s'aid crank shaft forming a plurality of variable volumetric spaces within the said pressure chamber; means having fluid inlet and fluid outlet ports carried by the said crank shaft rotatable in relation to the said pressure chamber, said inlet ports and said outlet ports each being symmetrically arranged with respect to the'axial length of said spaces so as to avoid unbalanced and thrust loads on the ends of said chamber and means.

l2. In a fluid transmission device comprising a housing, a pressure chamber therein, a crank shaft in rotatable relation to said housing, vanes pivotally connected to the said housing and to the crank of said crank shaft forming a plurality of variable volumetric spaces within the said pressure chamber, and means carried bythe said crank shaft adapted to rotate in relation to the said pressure chamber; an inlet port at each end of the aforesaid means adapted to communicate with the said volumetric spaces, each of saidinlet ports being characterized by the fact that they are opened due to the rotation of the said crank shaft to a-siz e in cross-sectional area equal to -said inlet apertures, thereby causing the saidA volumetric spaces within the said pressure chamber, each volumetric space communicating alternately with the said inlet apertures and with the said outlet apertures during a portion of each revolution of the said crank shaft, and means to introduce fluid under pressure into the said volumetric spaces symmetrically through the vanes to oscillate in said pressure chamber forcing said crank shaft to rotate about its axis distributinng the pressure forces so as to prevent unbalance or thrust between said crankshaft and 4; A fluid pump comprising a housing, a chamber therein, a crank shaft rotatable in said housing having a crank pin and carrying circular plates adjacent each end of said crank pin, said circular platesbeing adapted to rotate within the said chamber, an inlet aperture in each of said circular plates adapted to permit the en trance of fluid into the said chamber, cylindrical flanged portions carried upon the symmetrically arranged outer periphery of the said circular plates, outlet apertures in the said cylindrical Iii .the cross-sectional area of a plurality of the said volumetric spaces, and an exhaust outlet carried by the aforesaid means adjacent each end thereof.

3. A fluid motor comprising a housing, an annular pressure chamber therein, a crank shaft rotatable in said housing having a'crank pin substantially the length of said chamber and carrying circular plates adjacent each end of the crank pin, said circular plates being adapted to rotate flanged portionsadapted to permit the exhaust of fluid from the said chamber, vanes pivotally connected -to the said housing and to the said crank pin forming a plurality of variable volumetric spaces within the said chamber between said plates, each volumetric space communicating alternately with the said inlet aperture and with the said outlet apertures during a portion of each revolution of the said crank shaft, and means for rotating the said crank shaft to cause the said vanes to oscillate within the said chamber, thereby causing fluid introduced into the said volumetric spaces through the said inlet apertures to be discharged through the said outletapertures at an increased pressure.

5. A fluid motor of the positive displacement type comprising a housing, a pressure cylinder within the said housing, a crank shaft having a crank pm substantiauy the length of said cyunder and being rotatable in said housing, carrying circular plates adjacent each end of the crank pin serving as crank arms, said circular plates being adaptedv to rotate within the said pressure cylinder, opposed inlet ports in the said circular plates adapted to permit the entrance of fluid under pressure into the said pressure cylinder, cylindrical flanged portions carried upon the outer periphery of the circular plates, symmetri-k cally arranged outlet ports in the said cylindrical flanged portions adapted to 'permit the exhaust of fluid from the said pressure cylinder, vanes pivotally connected to the said housing and to the said crank pin provided with pressure sealing means Aat the pivotal connections and forming a plurality of pressure sealed expansible volumetric spaces axially within the-'said pressure cylinder between said plates, each volumetric space communicating alternately with the said inlet port and with the said outlet portduring a portion of each revolution of the said crank shaft, and means to introduce fluid under pressure into the said volumetric spaces through the said inlet ports, thereby varying the volume of the said spaces by causing the said vanes to oscillate within 'the said pressure cylinder forcing the said crank shaft to rotate about its axis.

6. A positive displacement device comprising a housing, a pressure chamber within said housing having fluid inlets and outlets, a crank shaft having a crank pin substantially the length of said chamber and being rotatable within the said pressure chamber, means'having symmetrically arranged intake ports and symmetrically arranged exhaust ports mounted upon the said crank shaft rotatable within the said pressure chamber and communicating with the said iiuid inlet and the said iluid outlet of the said pressure chamber respectively, a plurality of vanes pivotally connected to the said housing, and to the said crank pin forming a plurality of variable volumetric-spaces within the said pressure chamber, said plurality of variable volumetric spaces changing in shape and volume as the crank shaft revolves about its'axis, and means provided at said pivotal connections to pressure seal each of said volumetric spaces from adjacent spaces.

CALVIN M. BOLSTER..

REFERENCES orrnn The following references are of record in the ille of this patent:

UNITED STATES PATENTS Number Name Date 418,132 Isbell Dec. 24, 1889 1,818,430 Ricardo Aug. 11, 1931 2,139,856 Savage Dec. 13, 1938 2,336,344 Bullard Dec. '1, 1943 2,336,580 Yeatman Dec. 14, 1943' Certificate of Correction Patent No. 2,464,208. March 15, 1949.

CALVIN M. BOLSTER It is hereby certified that errors appear in the printed specification of the above numbered patent requrng correction as follows:

Column 4, line 44, for about is read about its; column 6, lines 10 and 11, claim 3, for distributinng read diam'lguting; lines 22 and 23, strike out symmetrically arranged and insert the same 1n hne 24, after the Word and comma plates,;

and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 11th day of October, A. D. 1949.

THOMAS F. MURPHY,

Assistant ommssioner of Patents. 

